Screening machine



Sept. 18, 1928.

J. O. BOWMASTER SCREENING MACHINE Filed NOV. 24, 1926 2 Sheets-SheetSum/mm 306W 0 oi owmaaarw, as 2/ Witness (If-lemma Sept. 18, 1928.

J. o. BOWMASTER SCREENING MACHINE Filed Nov. 2 1926 2 Sheets-Sheet ii mattooneqs Patented Sept. 18, 1928.

UNETED STATES PATENT 1 N wa BOWMASTER; F Q B'I QN .PENNWLVAIWM scnnnnrnerrnonnvn.

Application filed November 24, 1926. Serial No. 150,479.

means of an eccentric and pitinan.

It is one object of the invention to provide a screening machine of theclass set forth which will be rather simple and inexpensive, may beeasily and advantageously" nanufactured, and will be highly eiiicien-tand durable.

Another object is to provide a machine in which provision is made forquickly and easily removing a worn or injured screen and substitutinganother, it being understood. that such a substitution may also be madewhenever advisable, according to the charactor of material to bescreened.

With the foregoing in' view, the invention resides in the novel subjectmatter her'ein after described and claimed, the description beingsupplemented by the accompanying drawings.

Figures 1 and 2 are respectively a side elevation and a top plan view ofa screening machine constructed in accordance with my invention.

Figure 8 is a longitudinal sectional view on the plane of line 33 ofFig. 2.

Figure 4 is an elevation of the discharge end of the screen.

Figure 5 is a transverse sectional view on line 5.-5 of Fig, 1.

Figure 6 is a detail transverse section on line 66 of Fig. 2.

In the drawings above briefly described which illustrate the preferredform of construction, 7 designates a rectangular base frame whichcomprises two parallel side bars 8 preferably formed from angle metal,one end bar 9 formed of similar material, disposed at the discharge endof the machine, and a relatively heavy end bar 10 disposed at theopposite end of the machine and preferably formed of channel metal.

Two parallel, horizontally elongated, vertically positioned, side plates11 extend longitudinally of the side bars 8 and have their lower edgesriveted or otherwise secured thereto as indicated at 12. These platesare preferably stiffened at suitable intervals by vertical bars 13 ofangle metal, secured thereto by rivets or the like 14. The upper edgesof the plates 11 are secured by rivets 15 or other desired means, to theparaliel side bars 16 of a top frame 17, which frame, is preferablyformed from angle metal as shown. The frame 17 includes the two sidebars 16 and two end bars 18, one of the latter being disposed over theend bar 5) while the other is inwardly spaced from the end bar 10,leaving one end portion of the frame 7 projecting beyond the frame 17,this projecting end portion of frame 7 being effectively braced withrespect to the remaining portion of the general frame structure, by thenarrowed'ends 19 of the sine plates 11. I i I V Movably mounted betweenthe plates 11, 1s a screen-carrying frame EZO, said frame comprising twoside bars 21 having upstanding flanges 22, one end bar 23 having anupstanding flange 24;, and another end bar 25, the latter being free ofupstanding flanges but preferably having a downwardly pro; eoting flange:26. The bar 28 is disposed toward the end bar 10 ofthe base frame 7 andis secured by a bolt 27 or other desired means to the flexible end -28of .a pitman rod 29, this pitman rod being connected with an eccentric30 on the inner end of a drive shaft '31, the latter being rotatablymounted in appropriate bearingsSQ carried by the 'bar 10. This shaft 31may be driven in any desired manner and for illustrative purposes,

a pulley 83 has been shown upon its .outer end. i i Rocker arms '84: arepreferably employed to movably support the frame 20, the upper ends ofthese rocker arms being pivo-tally connected at 35 with the side barsQl,while the lower ends ofsaid rocker arms are prefera bly secured to asleeve 36 which extends transversely between and abuts the lowerportions of the side plates 11. A rigid shaft 37 passes through eachsleeve 36 and through openin s in the plates 11 and side bars 8, and theends of this shaft are provided in any suitable manner withprojectinghears or the like 38 which are secured thereto and arefastened to the bars 8 or other stationary parts of the general framestructure, in any suitable manner, as by rivets 39.

A screen 40 of any desired construction may be employed, said screenhaving side bars 11 and end bars 42 which lie upon the correspondingside and end bars of the screencarryingframe 20, all of said. side andend bars ll and 42, being provided with downwardly projecting flanges 43which engage the inner edges ofsaid side and ends bar of the frame 20.If desired, the side and end bars of frame may be detachably secured tothe corresponding bars of the screen 40, but in other instances, it maynot be necessary to securethese bars together, as the flanges 43,abutting the side and end bars of the frame 20, serve to hold the screen40 in proper relation with its carrying frame.

Two longitudinally disposed, aggregateguiding plates 44, declineinwardly from the upper edge portions of the side plates 11 and arehinged to the latter for upward swinging, as indicated at 45, and atrans verse, aggregate-guiding plate 46 declines inwardly from one endbar 18 of the top frame 17, being hingedly connected therewith asindicated at 47 NVhen the plates 44 and 46 are in the operativepositions shown in the drawings, they are disposed at the inner sides ofthe upstanding flanges 22 and 24. of the frame 20, so that all materialthrown into the screening machine, is by these plates properly guidedonto the screen. Anymaterial working out under the edges of these plates44 and 46, is, by means of the flanges 22 and 24, held against fallingfrom the frame 20, so that it must work to the dischar e end of thelatter, the bar 25 at this enc being free of upstanding flanges or otherprojecting means, so that free dis charge of all material which does notpass through the screen 40 may take place.

Whenever, it is necessary to substitute one screen for another, theplates 44 and 46 may be upwardly swung, giving access to the screen 40so that it may readily be removed from its carrying frame 20, permittinganother screen to be quickly and easily substituted.

While the operation of the machine will undoubtedly be clear, it may bebriefly explained that rotation of the shaft 31, causes the eccentricand pitman rod 29 to longitudinally vibrate the screen and its carryingframe 20, insuring effective separation of materials. As the throw ofthe eccentric 30 is slight, yielding of the pitman rod 29, at itsresilient portion 28 will permit the necessary vertical movement of saidrod, L

without the necessity of employing any pivotal connections.

The most essential characteristics of the machine have been hereindescribed, but it will be understood that changes may be made within thescope of the. invention as claimed. Moreover, mechanical details such asbraces 48, may be made use of at any desired points.

I claim:

1. A screening machine comprising a rec-V tangular base frame, a pair ofparallel vertically disposed side plates extending longitudinally of andsecured at their lower edges frame nearest said projecting end of the abase frame, a screen movably mounted between said side plates under saidaggregate guiding plates, and vibrating means for said frame including ashaft mounted on said projecting end of the base frame.

2. In a screening machine, a frame structure, a screencarrying framemovably mounted therein, a screen removably supported by saidscreen-carrying frame, and aggregate-guiding plates carried by'saidframe structure and extending down substantially to the screen, saidplates being permanently hinged at their upper edges to said framestructure above the screen for indivi dual pivotal movement upward fromthe screen to give access to said screen for the purpose of removing thelatter and substituting another. 7

In testimony whereof I have hereunto aflixed my signature.

JOHN OSCAR BQWMASTER.

